1. Field of the Invention
The invention relates to a dispenser unit and more particularly to a dispenser unit for extrudable material in which the dispensed material is metered so that for each actuation of the dispenser unit a specifically predetermined amount of material is dispensed and wherein the dispenser unit or the portion containing the extrudable material is dispensable.
2. Prior Art
The concept of holding an extrudable material in a container portion of a dispenser which is provided with a compression means which can be operated to exert an expelling or compression force on the extrudable material and thereby force the extrudable material through a nozzle in the container portion is well known. Such devices are described in U.S. Pat. Nos. 1,770,473 and 1,802,113 inter alia.
U.S. Pat. No. 1,770,473 discloses a dispenser having a button which is adapted to actuate a compression means within the container body. When the button is pushed, it turns a threaded rod in the compression means. The button itself also turns. When the button is released, it turns further. One of the problems associated with this structure is that it is extremely difficult to operate the dispenser with one hand since the turning of the button requires the use of both hands, i.e. one hand to hold the button, and the other to steady the dispenser, making it extremely difficult to apply the extrudable material to an object such as a tooth brush which also must be hand held.
The structure disclosed in U.S. Pat. No. 1,802,113 is rather complex in appearance, number of parts and interconnection between the parts so that it would not be feasible to incorporate this structure into a device which could be sold to consumers and which could be discarded when the extrudable material is evacuated from the dispenser.
It is toward elimination of these and other difficulties that the present invention is directed.